In the fraud trial of Elizabeth Holmes, the founder and former head of Theranos, emails and text messages have lately held center stage. Many of the communications in question were exchanged between Holmes and Ramesh Balwani, at the time her second-in-command, while the two were in a longtime romantic relationship.

Here’s the troubling part: At least some of the messages might not have been admissible had Holmes and Balwani been married rather than living together. That’s a distinction that probably made cultural sense in 1921 but in 2021 seems downright peculiar.

I have at times been unsympathetic to Holmes’s defense strategy. But I have also noted the way that the trial court’s evidentiary rulings — although certainly correct — have had the effect of punishing Holmes, a non-lawyer, for misunderstanding how attorney-client privilege works. Now it seems to me that the willy-nilly admission of the messages exchanged with her romantic partner — although, again, entirely correct on the existing law — is punishing her for not marrying him.

Marriage confers two evidentiary privileges. Non-lawyers are likely familiar with wrangles over whether one spouse can be forced to testify against the other. Less familiar but more important is the privilege that protects communications between spouses that they reasonably believe are private. It’s that second privilege that, if extended to cohabiting couples, might have turned the Theranos trial on its head.

Consider the following text message from Balwani introduced by prosecutors to show that Holmes was aware of problems at Theranos: “We built software to remove human error and human judgment. All day I saw these people use their judgments to work around our processes.”

Had the couple been married, it’s not obvious how the message would have come into evidence. The marital communications privilege has a number of exceptions, chief among them that it doesn’t apply when there is no reasonable expectation of privacy and that it cannot be used to hide a crime in which both spouses are involved.

Maybe the prosecution would have been able to show that, under the circumstances, any expectation of privacy was unreasonable, or that the statement was part of a larger conspiracy between the couple. But those aren’t easy claims to prove, and there’s a fair chance that the message would not have been admitted.

But because Holmes and Balwani weren’t married, the prosecution was required to jump through far fewer hoops. As experienced criminal defense lawyers predicted before the trial began, prosecutors were able to admit this and other messages “without the hindrance for the government of the marital privilege.”

Although I’m among those who still believes in the importance of marriage, I think it’s fair to say that American society is headed in a different direction. The decline of marriage may pose problems, but it’s still a fact. That’s why I’m also among those who think it’s past time to expand the privilege.

The privilege, a New York court wrote in 1894, “was founded upon a wise public policy, adopted and pursued for the purpose of encouraging to the utmost that mutual confidence which is the strongest guaranty of a happy marriage.” In other words, the rule protects our natural impulse to confide in the person we most love and trust. Makes sense. But we live in a time when that person may not be a spouse.

Over the years, many observers have argued that the privilege for confidential communications should be extended — for example, to those who cohabit. Some states grant the same protection to those in civil unions or common-law marriages, but thus far even judges who express sympathy for the claim have mostly refused to extend the privilege to the unmarried.(1)

It’s easy to see the challenge. Marriage is a bright line, a fact that’s true or false; the privilege exists or it doesn’t. Extending the reach of the protection might be asking too much of judges. The legal scholar Edward Stein, in a thoughtful 2012 paper, proposes that the law protect all those in serious relationships who “are in fact likely to communicate openly and provide each other with a refuge.”

Nice idea, but I still worry. Should we care how long the relationship has lasted? Suppose the confidence is shared in the course of a long-term and trusting extramarital affair? Such inquiries would seem to lie beyond the purview of what can reasonably be expected of courts adjudicating questions of privilege.

Some years ago, the legal scholar Sanford Levinson proposed a solution: Award every adult 20 or 30 “privilege tickets” that can be used over the course of a lifetime — distributed to friends, business partners, anyone with whom a person might seek to establish a truly confidential relationship. “Should you wish to talk intimately with your local bartender or hairdresser,” Levinson writes, “you would only have to give him one of your privilege tickets.” The court would have little trouble deciding the question of the privilege, because it would apply to anyone who had a ticket. Maybe Holmes and Balwani should have exchanged privilege tickets.

Or maybe there are better ideas out there. I hope we can think of some. Because whatever you might think of Elizabeth Holmes, there’s something sad and creepy, in 2021, about watching her sit in a courtroom as private messages between her and the person she once loved most are shared with the jury and with the world — all because they didn’t get married.

(1) One case refuses to grant the privilege to an unmarried couple who “merely have children in common” (merely!).

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Stephen L. Carter is a Bloomberg Opinion columnist. He is a professor of law at Yale University and was a clerk to U.S. Supreme Court Justice Thurgood Marshall. His novels include “The Emperor of Ocean Park,” and his latest nonfiction book is “Invisible: The Forgotten Story of the Black Woman Lawyer Who Took Down America’s Most Powerful Mobster.”

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